This invention relates to the production of precise images within metalized film substrates. It was known in the prior art to create images on metalized film substrates. One method was to print caustic fluid onto the substrate to erode the metal in the areas where the caustic fluid was printed, and then to rinse the caustic off the substrate to stop the process. The areas not printed with caustic fluid remained metallic and formed the desired image. This method did not work well for fine images, as the caustic fluid tended to “creep”, or to erode fine lines before the rinsing step could begin.
Another known method was to print a coating on the metalized film substrate and then to floodcoat the substrate with a caustic fluid. The caustic fluid eroded the metal in the areas where the coating was not printed. This method did not creep as much as the method described above. The coating, however, was not removable, so problems arose with this latter method if the substrate had to be laminated to another material, as the coating tended to create delamination problems between the two films. Additionally, if the final application involved packaged material that was incompatible with the coating, such as food or fragrances, this latter method was not available.
The method of the present invention ameliorates these problems.